Researcher Eshraq Anwar Ahmed Shaer successfully defended her master's thesis in Agricultural Biotechnology at Palestine Technical University – Kadoorie (PTUK) on March 18, 2024. Her thesis, titled “Genetic Variability in Wheat Genotypes Based on Root-to-Shoot Ratio and Molecular ISSR Markers,” was conducted at the Biodiversity and Environmental Research Center (BERC) laboratories under the joint supervision of Dr. Naser Jaber Sholi from PTUK and Prof. Mohammed S. A. Shtayeh from BERC. A grant from BERC financially supported her and her research.

Eshraq's research aimed to enhance wheat breeding programs by identifying genotypes with superior drought tolerance through a comprehensive evaluation of their root-to-shoot ratios and genetic diversity using Inter Simple Sequence Repeat (ISSR) markers. Her study provided critical insights for selecting drought-tolerant wheat genotypes and developing high-yielding varieties.

The research involved growing 30 wheat genotypes, including 20 bread wheat genotypes and 10 Palestinian durum wheat landraces, in pots containing 3 kg of field soil within a greenhouse setting. These plants were subjected to two water regimes—water-limited (WL) and well-watered (WW), over 54 days.

The study revealed significant trade-offs between shoot and root development under water-limited conditions. Plants demonstrated a coping mechanism by prioritizing root growth over shoot growth, evident from increased root biomass, length, and surface area, while aerial biomass, plant height, photosynthetic surface area (PSA), normalized difference vegetation index (NDVI), and total leaf area decreased under water stress.

In the molecular analysis, four markers—UBC1121100bp, UBC864400bp, UBC8411100bp, and Sola 5700bp—were found to be significantly associated with the root-to-shoot ratio (R/S). These markers accounted for 15.03% to 19.86% of the observed variation in R/S.

Shaer's findings provide a deeper understanding of the genetic diversity in wheat genotypes and their response to water-limited conditions. Bread wheat genotypes BW-9 and BW-14, along with durum wheat landraces DW-23, DW-25, and DW-26, emerged as promising lines exhibiting greater drought tolerance. Conversely, bread wheat genotypes BW-5, BW-11, and BW-20, and durum wheat landraces DW-22 and DW-30 were identified as more susceptible to drought stress.

These results offer valuable insights for wheat breeders aiming to select genotypes that are more resilient to drought, ultimately contributing to the development of wheat varieties with improved yield and survival under water-limited conditions.

Dr. Naser Sholi supervised the thesis from PTUK and Prof. Mohammed Saleem Shtayeh from BERC. The examination committee included Dr. Rana Majed Jamous and Prof. Mazen Salman.